Posts: 2
Threads: 1
Joined: Feb 2012
I have a 72 Mach1.
When I turn on the headlights the gages all go up.
ie. the fuel gage goes from 1/4 to 1/2.
Anyone had this problem?
Posts: 5,003
Threads: 2,097
Joined: Aug 2009
This is a total guess but Id check your voltage regulator first.
Posts: 282
Threads: 50
Joined: Mar 2011
I had the same kind of a issue with a truck of mine , found out the circuit board had a bad spot in it, I would turn my lights on and all the gauges would go haywire.
Posts: 3,222
Threads: 197
Joined: Nov 2009
The headlight also dims the instrument panel lights. Try dimming the lights all the to off and then try turning on the headlights. If the gages do not go haywire you probably need a new headlight switch. Not sure this is your problem, but worth a try.
Posts: 194
Threads: 6
Joined: Jan 2011
Check your body ground and the head and tail light grounds..
Also possible bad instrument voltage regulator.
Posts: 4,181
Threads: 46
Joined: Jan 2011
Welcome STOY.
Glad to have you with us. It sounds like you have received some very good information and ideas. Check it out and see what you come up with. Let us know the outcome.
Posts: 2
Threads: 1
Joined: Feb 2012
Hi all
Thanks for the thoughts on my problem
I`ll let you know what happens
![[-]](https://mach1club.com/images/collapse.png "[-]")
